I've had both personal and side-line experience with 3-4 sets, or more.
Regardless of ratings, they are as quiet, in my opinion, as Symmetry, which
is a cheaper, lower-mileage tire.  Usually, the higher-mileage tires are
noisier and tend to have a harsher bump over road defects.
   But to gain the extra mileage, to enjoy the smooth ride, and enjoy the
mental superiority(as afforded by their ratings) over the less-expensive
ones, I'd be happy to pay the extra.  If I had my choice--which I don't
always, as I trade so often and often use whatever is on the 'new' car--I'd
wear Harmony's on everything.  Good tires with tolerable prices.
   Actually, several years ago, I bought a set of LeSabre Limited wheels,
for our used but just-bought LeSabre, and installed a new set of Harmony's
which I installed & ran on until it was time for another car; put on the
originals, sold it, and bought a year-newer LeSabre and installed the
Michelins-and-wheels on it; etc.  Used them on several LeSabres, and they
even now look almost new.  (Wife wanted an 05 Chrysler minivan w/Sto'nGo
seats this time.  Still trying to figure out how to mount the wheels and
Mich's on the van!)
   Good luck & enjoy the Avalon, whatever tires you buy.  I certainly feel
you'll be happy w/the Harmony's.  Be sure and verify proper pressure with a
good gauge and check them often, when cold, like 1st Sunday morning of each
month--good habit plus it's cheaper to run on air than on rubber.  s

Hi-
If you buy Michelins, be very careful going around turn 13.
Seriously, get a set of Bridgestone Turanza LS-V's for your Toyoto (he he
he) instead -better all around tire imo than the crap Michelins.